Weather is caused by a bunch of molecules. Since we don’t know exactly how the molecules will behave, weather forecasters make lots of models and then look at the average. That’s why they say things like “There’s a 70% chance of rain”—perhaps they’ve made 100 models, and it rained in 70 of them. (As described by Nate Silver in The Signal and the Noise.)
If we knew exactly what each molecule was, though, we could predict the weather with perfect accuracy.
Now, consider the extent to which the course of your life is determined by prior causes.
As we’ve discussed, you have no free will (because your choices are based on your thoughts, and your thoughts are based on your physical body/brain chemistry and life experience. Since you cannot control those things—and hence cannot control your thoughts—you cannot control your actions, and therefore you do not have free will).
So everything you do is “determined by prior causes” (as Sam Harris puts it). By that logic, though, it seems that these prior causes form a chain that can be traced back to the first living thing/material substance/the beginning of the universe.
Does that mean that if you could go back to the beginning of the universe and know everything about the components of the world in that state, you could predict everything that would ever happen?
I’m not sure. I keep hearing that the universe is inherently random. (For instance, evolution depends on the occurrence of “random mutations”—right?) So doesn’t it seem like randomness would make it impossible to predict what will happen based solely on the starting conditions?
It seems like if this “randomness” (as I understand it) really is random, then we shouldn’t ever be able to predict the weather. And yet Nate Silver says we could, if we just knew everything about every component of the initial conditions.
But then maybe that’s just the weather, and randomness in the course of human lives/evolution/the universe is different (and genuinely unpredictable)…
In short: I’d like to know the extent to which randomness (in the course of human lives/the universe) is actually random.
Thanks to my new friend Adam for the conversation that inspired this post.